Abstract
Floor drains for the rain water drainage are installed in balcony and corridor at the buildings. The dispersion phenomenon of rain water happens in the existing drain for relay when rain water is drained directly from the rooftop to the relay drain. In recent years, the local heavy rain by the abnormal weather is increasing. In that case, the balloon phenomenon of rain water happens when the rainfall increases.In order to reduce this phenomenon roughly, we researched floor drains of funnel structure.
